Phalanx

Polartec® Alpha® Direct is an active-insulation fabric originally developed for US Special Forces to cope with the stop-go pace of active combat, where effort and body heat change by the minute. It's a grid-knit insulation that needs no separate backing fabric, so it can sit next-to-skin or be layered over a base layer without extra bulk. On the Phalanx Fleece and Phalanx Fleece Crew Neck, that means the fleece breathes fast when you're working hard and holds warmth as soon as you stop, rather than trapping heat regardless of effort.

Polartec® Alpha® Direct is built to breathe, not just to trap heat. Down insulation gives the best warmth-to-weight ratio when you're static, but it loses performance once damp and traps heat even when you're working hard. Synthetic insulation with a backing fabric solves the damp problem but adds bulk and cuts breathability. Alpha® Direct removes the backing fabric altogether, so the Phalanx Fleece range vents heat during high-output effort and still holds warmth once you slow down.

Yes. A fleece midlayer like the Phalanx Fleece or Phalanx Fleece Crew Neck is built for exactly the kind of stop-go effort hiking involves, climbing hard on an ascent, then cooling down fast on a ridge or at a rest stop. Because Polartec® Alpha® Direct breathes without a backing fabric, it clears heat and moisture during the climb and still holds warmth when the pace drops.

Both fleeces work as a standalone midlayer or under a shell. The full-zip Phalanx Fleece adds a hood for extra warmth around the neck and head when moving between exposed and sheltered ground, and its centre-front zip makes it easy to vent on the move. The Phalanx Fleece Crew Neck is the lower-profile option, cut closer to the body with a dropped hem and cord adjuster for a tailored fit under a jacket.